Ethylene/butylene

As more complex multicomponent blends are being developed for commercial appHcations, new approaches are needed for morphology characterization. Often, the use of RuO staining is effective, as it is sensitive to small variations in the chemical composition of the component polymers. For instance PS, PC, and styrene—ethylene/butylene—styrene block copolymers (SEES) are readily stained, SAN is stained to a lesser degree, and PET and nylons are not stained (158,225—228). 

Most elastomers that are used for nylon modification contain a small amount of maleic anhydride (0.3 to 2%). In the melt blending process, these elastomers react with the primary amine end groups in nylon, giving rise to nylon grafted elastomers. These grafts reduce the interfacial tension between the phases and provide steric stabili2ation for the dispersed mbber phase. Typically, thermally stable, saturated mbbers such as EPR, EPDM, and styrene—ethylene/butylene—styrene (SEBS) are used. 

I indicates compatible with polyisoprene segments B, compatible with polybutadiene seg-ments EB, compatible with poly (ethylene—butylene) segments and S, compatible with poly-styrene segments. 

Thermoplastic block copolymers were used for pressure-sensitive and hot-melt rubber adhesives as from the middle sixties. These adhesives found application in packaging, disposable diapers, labels and tapes, among other industrial markets. The formulation of these adhesives generally includes an elastomer (generally containing styrene endblocks and either isoprene, butadiene or ethylene-butylene midblocks) and a tackifier (mainly a rosin derivative or hydrocarbon resin). 

PET = polyethylene terephlhalene SEES = styrene-ethylene butylene-styrene PSO = polysulfone. For other abbreviations see text. 

Figure 8-7. The Phillips Petroleum Co. process for producing 2-butene and ethylene from propylene (1) metathesis reactor, (2) fractionator (to separate propylene recycle from propane), (3, 4) fractionator for separating ethylene, butylenes, and Cg. ...

Saturated styrene-ethylene-butylene-styrene (SEBS) and styrene-ethyl-propyl-styrene (SEPS) are produced by hydrogenating SBS and SIS block copolymers, respectively, before they are recovered from the solution [3]. 

Copolymerization of ethylene and styrene by the INSITE technology from Dow generates a new family of ethylene-styrene interpolymers. Polymers with up to 50-wt% styrene are semicrystalline. The stress-strain behavior of the low-crystallinity polymers at ambient temperature exhibits elastomeric characteristics with low initial modulus, a gradual increase in the slope of the stress-strain curve at the higher strain and the fast instantaneous recovery [67], Similarly, ethylene-butylene copolymers may also be prepared. 

Blend with Isotactic Polypropylene and Styrene-Ethylene-Butylene-Styrene... 

FIGURE 20.10 (a,b) Phase images of cryo-ultramicrotomed surfaces of triblock copolymer styrene and ethylene-butylene (SEES) samples of neat material and loaded with oil (40 wt%), respectively. (c,d) Phase images of film of triblock copolymer poly(methyl methacrylate-polyisobutylene-poly(methyl methacrylate) (PMMA-PIB-PMMA) immediately after spin-casting and after 3 h annealing at 100°C, respectively. Inserts in the top left and right comers of the images show power spectra with the value stmctural parameter of microphase separation. 

SEES with oil leads to the transition from lamellar morphology to micellar morphology [15]. This transformation is reflected in the above images of pure SEES and its SEES/oil = 60 40 composition. The loading leads to an increase of the structural factor from 21 to 53 nm. Therefore, the incorporation of oil to ethylene-butylene blocks induced larger separation of micelles formed predominantly by styrene blocks. 

FIGURE 20.15 Phase images of samples of triblock copol3mier styrene and ethylene-butylene (SEES) filled with clay particles (5 wt%) with (a) poor mixing and exfoliation and (b) fine distribution of clay layers. 

Abbreviation for styrene-ethylene-butylene-styrene block copolymer, a thermoplastic elastomer. 

In this type of styrenic TPE the polybutadiene mid-block used in the SBS types is replaced with ethylene-butylene which is saturated ... 

Ethylene-butylene, glass transition and melting temperature for soft/hard segments, 7 649t Ethylene-butylene-isobutylene,... 

Polystyrene-6Zoc -poly(ethylene-butylene)-block- polystyrene, 7 647 Polystyrene-Woe/ -poly(> .-butyl acrylate), 7 646... 

SEBS Poly(styrene-b-ethylene butylene-b-styrene)... 

Basura, V. I., Chuy, C., Beattie, P. D. and Holdcroft, S. 2001. Effect of equivalent weight on electrochemical mass transport properties of oxygen in proton exchange membranes based on sulfonated a,j3,j3-trifluorostyrene (BAM) and sulfonated-styrene-(ethylene-butylene)-styrene triblock (DAIS-analytical) copolymers. Journal ofElectroanalytical Chemistry 501 77-88. 

One of the olefins, propylene, is a commercial starting point for all those compounds. Commercial routes from ethylene, butylene, etc., have not been developed. 

Presently, two commercial (or semicommercial) PEMs are based on styrene or styrene-like monomers BAM from Ballard, and Dais Analytic s sul-fonated styrene—ethylene—butylene—styrene (SEBS) membrane. Ballard Advanced Materials Corporation introduced a styrenic membrane based on a novel family of sulfonated copolymers incorporating a,/3,l3-trifluorostyrene and substituted a,y3, -trifluoro-styrene comonomers. These are registered as BAM membranes, and their general formula is given in Figure 3. 

By rapid expansion of supercritical propane solution (RESS), and isobaric crystallisation (ICSS), isotactic polypropylene and ethylene-butylene copolymers were precipitated from the supercritical solution. The RESS process produced microfibres with a trace of microparticles, while the ICSS process produced microcellular products. Improvement in thermal stability was achieved by first synthesising a thermoplastic vulcanisate from polypropylene and ethylene-propylene-diene terpolymer from a supercritical propane solution, followed by RESS. 28 refs. 

Poly(propylene-co-1 -hexene) Poly(ethylene-co-vinyl acetate) Styrene-ethylene-butylene-styrene - - oil Styrene-butadiene-styrene -I- oil Nitrile rubber Nitrile rubber -I- diluent ... 

C-Flex Linear block styrene copolymer with ethylene-butylene Consolidated Polymer Tech... 

Elexar Linear styrene block copolymer with ethylene-butylene Teknor Apex... 

Hy (and related copolymer with butadiene or ethylene butylene Olefin fibers Fiber Vision Prods. 

SEES Styrene-ethylene-butylene-styrene block copolymer. 

Bui et al. (3) prepared glossy cosmetics consisting of poly(styrene-h-ethylene) and poly(styrene-/ -ethylene)-/ -(butylene-/ -styrene) blended with propyl silses-quioxane wax. 

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